So I am preparing to move into my new abode and get something going, I know I'll be going hydro scrog. My question is would I (in theory) net more weight using 3x400w hps, or 2x600w hps?(assuming id have 3 smaller tables or 2 larger respectively)
2x600w. 600w is the "sweet spot" of HPS lighting, it is most efficient and therefore puts out more lumens per watt then lower or higher rated bulbs.
i'd say it depends on your size. if you have a larger area more lights would be better as the foot print of the lights wont cover evreything